The present invention relates to a power component assembly for mechatronic integration of power components.
Electric drive systems are employed in many applications. The power ratings of such drives can range from microwatts (e.g., for wristwatches) to very high power ratings in the megawatt range (e.g., for locomotives, rolling mills, etc.). Such drive systems encompass a large range of applications, ranging from the simplest drive for toys to demanding position controls in machine tools.
An electric drive system includes at least one motor which receives electric energy from the power grid and converts the electric energy into rotational energy, and optionally a gear. Regulated or rotation-speed-adjustable drives are mostly used for larger drives or for more demanding applications, or if the maximum drive power is not always required. The electric motor in a regulated drive is operated via a power regulator, whereby a controller ensures that the desired process parameters are maintained. An electric power regulator is mostly implemented as a single unit that includes both the required power electronics and the associated signal processing. Such units are referred to, for example, as “converters” or “inverters”. This term applies to the entire unit and not just to the power section.
The components used in the power electronics include diodes, thyristors, power transistors and MOSFETs, which are used in particular for high switching frequencies (of up to 1 MHz) and small voltages (of up to approximately 400V), as well as IGBTs (Insulated Gate Bipolar Transistors) for high power and moderate switching frequencies (3 kHz . . . 100 kHz). Modern IGBTs are available for high voltages (2 kV) and currents. IGBTs have found widespread applications in the drive technology. Modern inverters for operating asynchronous and synchronous machines in the power range from a few 100 W to the MW-range use almost exclusively IGBTs.
The power components are arranged in modules which can include individual switches and/or integrated switching assemblies The configuration and connection of the modules has to provide electrical isolation as well as a compact, preferably flat, installation size and advantageous thermal properties. At the same time, the cost for materials and processes has to be kept low while maintaining a high long-term reliability and a small failure rate. Moreover, a large power range should be covered with the smallest possible number of module configurations.
A manufacturer inserts the power components into a housing, and the terminals on the chips are connected with the external terminals of the housing. The dimensions of the housings and the assembly of the contact are standardized for the integrated circuits or chips used in low-power and communication devices, so that products from different manufacturers can be readily interchanged. No such standardized housing configurations exist for higher power electronic devices.
When a new module is developed, its functionality can be improved by optimally combining of the mechanical and electronic components through, e.g., mechatronic integration. The various parts of the applications have to cooperate for the integration to be successful by providing adequate pathways for the electrical current. Moreover, the power components should be arranged so that they are electrically isolated from each other and the heat of the power components is properly dissipated. In addition, the modules should be easy to install and operate reliably.
Power components from different manufacturers often differ with respect to their housing profile. The suitability of all components for mechatronic integration in the module must therefore be individually tested. The finally selected power component has in general a complex housing and may still not be optimized for a mechatronic integration in a realistic application.
In an actual system, the heat dissipation from the power components may still not be optimized because the origin of the heat loss cannot be spatially resolved. Frequently, the switching circuits in the power components have to be electrically insulated from each other, requiring a larger number of component and/or components with a more complex configuration. As a result, the entire system becomes less robust, has an increased installation volume and an inadequate thermal resistance (Rth).
In general, a distinct solution has to be found for each newly developed module in order to balance to requirements of the power component housing shape with the targeted application.
It would therefore be desirable and advantageous to provide an improved power component assembly, which obviates prior art shortcomings and specifically allows a mechatronic integration of different power components for an application.